Social Media Marketing

It says I searched some facebook redirect link thing, which turns up no results, and I can't even get on my homepage long enough to click on something before it redirects. It's getting really frustarting! I tried cleaning my internet files, etc. What do I do?

I have four sites I'm trying to block in the hosts file. However, Myspace and Facebook keep removing themselves from the hosts file. Yet, the other two remain on there and continue to block those sites fine.

Whenever I visit twitter, I have a bunch of new tweets, and it's really difficult to keep up with them, and know which tweets are new and I have already read. How can I keep up with them?

I do not know what Twittering means, nor what is a Twitter is. Please tell me what it is.